Kamera implementiert und Preview im Interface

Zusätzlich eintragen der Berechtigungen und der extra Klasse KameraAktivitaet im Manifest eingetragen

app/build.gradle

         sourceCompatibility JavaVersion.VERSION_1_8
         targetCompatibility JavaVersion.VERSION_1_8
     }
+    namespace 'com.example.greenwatch'
 }
 
 dependencies {
     testImplementation 'junit:junit:4.13.2'
     androidTestImplementation 'androidx.test.ext:junit:1.1.5'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
+
+    def camerax_version = "1.2.3"
+    implementation "androidx.camera:camera-camera2:${camerax_version}"
+    implementation "androidx.camera:camera-lifecycle:${camerax_version}"
+    implementation "androidx.camera:camera-view:${camerax_version}"
+
 }

app/src/main/AndroidManifest.xml

 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.example.greenwatch">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <uses-permission android:name="android.permission.RECORD_AUDIO"/>
+    <uses-permission android:name="android.permission.CAMERA"/>
+    <uses-permission android:name="android.permission.BLUETOOTH"/>
+    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
+    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
+    <uses-permission android:name="android.permission.INTERNET" />
+
+    <uses-feature android:name="android.hardware.camera"/>
 
     <application
         android:allowBackup="true"
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+
+        <activity android:name=".KameraAktivitaet" />
+
     </application>
 
 </manifest>

app/src/main/java/com/example/greenwatch/Kamera.java

-package com.example.greenwatch;
-
-public class Kamera {
-}

app/src/main/java/com/example/greenwatch/KameraAktivitaet.java

+package com.example.greenwatch;
+
+import android.graphics.ImageFormat;
+import android.media.Image;
+import android.os.Bundle;
+import android.util.Size;
+
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.camera.core.CameraSelector;
+import androidx.camera.core.ImageAnalysis;
+import androidx.camera.core.Preview;
+import androidx.camera.lifecycle.ProcessCameraProvider;
+import androidx.camera.view.PreviewView;
+import androidx.core.content.ContextCompat;
+
+import com.google.common.util.concurrent.ListenableFuture;
+
+import java.util.concurrent.ExecutionException;
+
+public class KameraAktivitaet extends AppCompatActivity {
+    private PreviewView previewView;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_demo_kamera2_nebenaktivitaet);
+        previewView = findViewById(R.id.previewView);
+        final ListenableFuture<ProcessCameraProvider> cameraProviderFuture = ProcessCameraProvider.getInstance(this);
+        cameraProviderFuture.addListener(() -> {
+            try {
+                bindImageAnalysis(cameraProviderFuture.get());
+            } catch (ExecutionException | InterruptedException e) {
+                e.printStackTrace();
+            }
+        }, ContextCompat.getMainExecutor(this));
+    }
+
+    private void bindImageAnalysis(ProcessCameraProvider cameraProvider) {
+        ImageAnalysis.Builder builder = new ImageAnalysis.Builder();
+        builder.setTargetResolution(new Size(640, 480));
+        builder.setBackpressureStrategy(ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST);
+        ImageAnalysis imageAnalysis = builder.build();
+        imageAnalysis.setAnalyzer(
+                ContextCompat.getMainExecutor(this),
+                imageProxy -> {
+                    int imageFormat = imageProxy.getFormat();
+                    if (imageFormat == ImageFormat.YUV_420_888) {
+                        Image image = imageProxy.getImage();
+                    }
+                    imageProxy.close();
+                });
+
+        Preview preview = new Preview.Builder().build();
+        CameraSelector cameraSelector = new CameraSelector.Builder().requireLensFacing(CameraSelector.LENS_FACING_BACK).build();
+        preview.setSurfaceProvider(previewView.getSurfaceProvider());
+        cameraProvider.bindToLifecycle(this, cameraSelector, imageAnalysis, preview);
+    }
+}
+

app/src/main/java/com/example/greenwatch/MainActivity.java

 package com.example.greenwatch;
 
-import androidx.appcompat.app.AppCompatActivity;
-
+import android.content.Intent;
+import android.content.pm.PackageManager;
 import android.os.Bundle;
+import android.widget.Button;
+
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.core.app.ActivityCompat;
+import androidx.core.content.ContextCompat;
 
 public class MainActivity extends AppCompatActivity {
+    private static final int RECHTEANFORDERUNG_KAMERA = 10;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
+        Button kameraStarten = findViewById(R.id.button_camera);
+        kameraStarten.setOnClickListener(v -> {
+            if (istZugriffAufKameraErlaubt()) {
+                starteKameraAktivitaet();
+            } else {
+                zugriffAufKameraAnfordern();
+            }
+        });
+    }
+
+    private boolean istZugriffAufKameraErlaubt() {
+        return ContextCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED;
+    }
+
+    private void zugriffAufKameraAnfordern() {
+        ActivityCompat.requestPermissions(this,new String[]{android.Manifest.permission.CAMERA}, RECHTEANFORDERUNG_KAMERA);
+    }
+
+    private void starteKameraAktivitaet() {
+        startActivity(new Intent(this, KameraAktivitaet.class));
     }
 }

app/src/main/res/layout/activity_main.xml

     android:layout_height="match_parent"
     tools:context=".MainActivity">
 
-    <TextView
+    <Button
+        android:id="@+id/button_camera"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:text="Hello World!"
+        android:text="Kamera starten"
         app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintLeft_toLeftOf="parent"
-        app:layout_constraintRight_toRightOf="parent"
-        app:layout_constraintTop_toTopOf="parent" />
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.129"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent"
+        app:layout_constraintVertical_bias="0.931" />
+
 
 </androidx.constraintlayout.widget.ConstraintLayout>

build.gradle

 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 plugins {
-    id 'com.android.application' version '7.1.3' apply false
-    id 'com.android.library' version '7.1.3' apply false
+    id 'com.android.application' version '8.0.0' apply false
+    id 'com.android.library' version '8.0.0' apply false
 }
 
 task clean(type: Delete) {

gradle.properties

 # Enables namespacing of each library's R class so that its R class includes only the
 # resources declared in the library itself and none from the library's dependencies,
 # thereby reducing the size of the R class for that library
-android.nonTransitiveRClass=true
+android.nonTransitiveRClass=true
+android.defaults.buildfeatures.buildconfig=true
+android.nonFinalResIds=false

gradle/wrapper/gradle-wrapper.properties

 #Thu May 11 14:50:16 CEST 2023
 distributionBase=GRADLE_USER_HOME
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0-bin.zip
 distributionPath=wrapper/dists
 zipStorePath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME